This invention relates generally to shaft couplings, and more particularly to apparatus for housing a shaft coupling.
Frequently, a turbine will be used to drive a compressor, or a first compressor, which is being driven by a turbine, will be used to drive a second compressor. Typically, units such as turbines and compressors include a casing or shell enclosing the working parts of the unit, and a rotatable shaft extending outward from the casing. In order to use one of the units to drive a second unit, the shaft of the driving unit is connected, by means of a shaft coupling, to the shaft of the driven unit wherein rotation of the former shaft rotates the latter shaft. When a first compressor drives a second compressor, often vapor will be passed from the driving compressor to the driven compressor for further compression. In this case, the portions of the shafts which extend out from the casings and the shaft coupling which connects these shafts may be housed or covered by a shaft coupling housing which guides vapor from the first compressor to the second compressor.
Prior art housings for shaft couplings typically include a sleeve type member and an axially split housing member. To form the housing, the sleeve member is positioned around a first shaft before the shafts are coupled, and the sleeve member is connected to a first shaft casing. The sleeve only partially covers the shaft, leaving room to insert a coupling member between the shafts. Once the shafts are coupled, the axially split housing member, which includes a top section and a bottom section, is used to enclose the shafts and the shaft coupling. More specifically, the bottom section of the housing member is positioned below the shafts and shaft coupling, the top section is positioned above the shafts and shaft coupling, and the two sections are joined together, usually by bolting the sections together.
The axially split housing member often has a substantial axial length. This is generally the case because the area which the housing member covers must be large enough so that there is sufficient room to insert a coupling member into the area and to join the coupling to the individual shafts. Because of this relatively large axial length, a relatively large number of securing devices such as bolts are usually needed to tightly join the top and bottom sections of the housing member. These securing devices represent an expense. Further, because of the large number of securing devices involved, assembly and disassembly of the housing member, for example to replace or repair the shaft coupling, are relatively cumbersome and time consuming tasks, involving a considerable amount of expensive manual labor.